Ross Hauser, MD

In this article, we will explore the various treatment options that can help people today with chondromalacia patella, patellofemoral pain syndrome, or “runner’s knee” get back to their sport or activities. We will discuss the various causes of a traumatic knee injury, degenerative arthritis, sudden onset from overtraining, and the development of the pain syndrome following arthroscopic knee surgery.

Article outline:

• At some point, you decide that you can no longer manage this pain on your own with over-the-counter pain relief medications, knee braces, and ace bandages so you go to a health care provider.
• I do not understand what my at my problem is. “No matter what you call it, you have pain.”
• Doctors are more aware that patellofemoral pain is a confusing diagnosis.
  • The many problems in the knee that surround a patella diagnosis.
  • A pain that no one understands and in some cases, no one believes.
• This study’s aim was to “determine whether the evidence supports manifestations of central sensitization in individuals with Patellofemoral pain. (Simply, is this real?)
• Intent to study neurophysiological changes of brain and spinal cord in individuals with patellofemoral pain.
• Patellofemoral Pain Syndrome – Why women feel more pain.
• You may be surprised that the health care provider is recommending the same over-the-counter pain medications and knee braces and other knee pain , treatments you tried on your own that did not work for you.
• Physical therapy will typically fail if the strong connective ligament and tendons needed to provide resistance to maximize muscle gain and knee stability are not strong enough.
• Exercise can work in some with Patellofemoral pain
• Using painkillers – Doctors issue concerns and warnings – Approximately one in five adolescents with longstanding knee pain reported pain medication use.
• Patients waiting for an MRI delay exercise and physical therapy while waiting outcomes. Some researchers say this is no good.
  • The MRI will not see your knee pain getting worse and it will confuse you and your doctor.
• Will a knee brace or tape hold my knee together, even with “appropriate caution?”
• Retraining the way you run? A new study kicks off to explore gait training.
• “The patient often bounces from practitioner to practitioner, physiotherapist as well as surgeon, for some relief of symptoms.”
• When knee pain is worse than it should be and nothing is working, what next?
• Hip and knee strengthening (physical therapy and exercise) may not be adequate to heal the problem. Are they actually making it worse? Especially in women?
• Patellofemoral pain syndrome impacts the whole body.

Surgery and other treatments

• Patellofemoral cartilage surgery?
• Research: Unrealistic expectations of patella pain syndrome surgical success are common and will lead to disappointment.
  • The prevalence and change in neuropathic pain or pain catastrophizing before and 12 months following patellar stabilization surgery for patellofemoral instability
  • “This rise in surgical intervention has brought about various complications.”
  • Younger patients have better surgical results, but what do you do with older patients? Patellofemoral arthroplasty?
• Botulinum toxin injections as a salvage therapy.
• Solving Patellofemoral Pain Syndrome is recognizing the problem of knee instability.
• You must treat the whole knee to fix the problem of patella pain.
  • Comprehensive Prolotherapy for Patellofemoral Pain Syndrome – treating the whole knee.
  • Platelet Rich Plasma Therapy.
  • Discussion of stem cell therapy.

You started experiencing knee pain, your kneecap is sliding out of place, you can no longer exercise or walk down a flight of stairs without pain. You need help.

Above I discussed the various ways your knee pain may have developed. Over the years we have heard many stories and case histories from people about their knee pain and have been able to provide a composite view of the challenges many people face.

If you are like the many patients we see, you started experiencing knee pain and that pain became the first step in a long journey of treatments. At first, it was not quite a sharp pain but rather a chronic dull pain that seemed to center on the front of your knee around the knee cap. Then it started to get worse and it started to affect the way you move, work, and participate in sport or exercise.

• If you are athletic, run, and work out, you may have suffered a spike in pain and discomfort especially after running or playing in sports involving jumping. Especially if you are running downhill. You will also notice the same pain when walking down a flight of stairs, The key to your pain seems to be when you are moving downward.
• You may have suffered a spike in pain during exercises involving the use of “squats.”
• Pain may have become intense if you decide to drastically change your sports activity or exercise to be “more challenging.” At some point, intensive workouts or running had to be stopped.
• You feel as if your kneecap slides around too much.
• Younger athletes, too young to have severe osteoarthritis, may have some upper and outer knee pain and they will seek physical therapy. This is a clue of kneecap instability. In this case, physical therapy is being used to strengthen the surrounding muscles, the quadriceps, to keep the knee cap correctly tracking. These younger athletes are in our office because physical therapy is not helping as much as they need it to.

You may have been suggested to exercise and get physical therapy, and were told this will probably help you. You may have been the person that it did not help. Your story may go something like this:

I have chondromalacia patella. It has been bothering me for a year and a half. I have been doing the strengthening exercises that were recommended to me but I am not getting results or relief from the pain. At first, it was only my left knee that was the problem. Now I have swelling and discomfort in my right knee too. My situation is getting worse day by day. I have pain when I walk long distances or stand still for a while. I have avoided all my sports activities. All of this occurred when I started to run long distances on the treadmill.

What would we do in a case like this? This is explained below.

But I am not an athlete, it hurts just the same:

• In non-athletic patients, a vicious cycle may have started. You had knee pain and the knee pain makes you sit for prolonged periods of time.
• The pain is getting worse and your sitting becomes much more frequent. When you try to get up from a chair your knee pops and cracks and there can be intense pain on standing. You sit back down.
• Your situation is in a downward spiral of intense and frequent knee pain. Worse, your doctor may not believe how bad your knee hurts. See below.

The development of Patellofemoral Pain Syndrome after arthroscopic knee surgery will be discussed below.

What are we seeing in this image? A source of knee pain.

This simple illustration may explain a lot of complex pain. On the left, we have a normal knee joint. On the right, we see inflamed chondral cartilage, the cartilage of the back of the knee cap, and in the knee groove where the knee cap is supposed to slide.

At some point, you decide that you can no longer manage this pain on your own with over-the-counter pain relief medications, knee braces, and ace bandages so you go to a health care provider.

You may have a discussion with your healthcare provider, in this discussion, he/she may discuss with you chondromalacia patella. (Chondro means cartilage, malacia means breakdown, and patella means kneecap.) Thus, chondromalacia patella refers to cartilage breakdown underneath the kneecap. Your health care provider may also call this, patellofemoral dysfunction or patellar-tracking dysfunction. If your pain is severe, he/she may discuss with you Patellofemoral Pain Syndrome. If you are an athlete, your clinician may call your condition “runner’s knee,” which is simply a broad description of knee pain that is coming from the knee cap area attributed to overuse.

Whatever it is called, this problem you have is a problem that began as a patellar-tracking problem. You are having pain when the underside of the kneecap is abnormally rubbing against the thigh bone.

I don’t understand what my problem is. “No matter what you call it, you have knee pain.”

People who have patella-related pain are sometimes confused by diagnosis, treatment plan, and a general understanding of what is going on in their knee. Their frustration in multiple diagnoses and a lot of testing is in fact displayed in the statement, “whatever you call it, I have pain.”

A study in the journal Clinics in Sports Medicine (1) offered this challenge to doctors and patients in understanding problems of the knee centered on the patella.

“Patellofemoral pain syndrome is a frequently encountered overuse disorder that involves the patellofemoral region and often presents as anterior (front) knee pain. Patellofemoral pain can be difficult to diagnose. Not only do the etiology, diagnosis, and treatment remain challenging, but the terminology used to describe Patellofemoral pain is used inconsistently and can be confusing. Patellofemoral pain syndrome (PFPS) seems to be multifactorial, resulting from a complex interaction among intrinsic anatomic and external training factors. Although clinicians frequently make the diagnosis of Patellofemoral pain syndrome, no consensus exists about its etiology or the factors most responsible for causing pain.”

That study was published in 2010 and reflects a problem in 2010. Certainly, things have changed in eleven years. Perhaps what has changed is that doctors are more aware that Patellofemoral pain is a confusing diagnosis. But confusion is still there in 2026 as we will see below.

Doctors are more aware that Patellofemoral pain is a confusing diagnosis

In 2017, building on this theme, of difficulty in diagnosis and difficulty in understanding how to stop the progression of knee deterioration and provide treatment, doctors wrote in the Open Access Journal of Sports Medicine,(2) of the problems that need to be recognized in athletes.

“Patellofemoral pain is a very common problem in athletes who participate in jumping, cutting, and pivoting sports. Several risk factors may play a part in the pathogenesis of Patellofemoral pain. Overuse, trauma, and intrinsic risk factors are particularly important among athletes. Physical examination has a key role in Patellofemoral pain diagnosis. Furthermore, common risk factors should be investigated, such as hip muscle dysfunction, poor core muscle endurance, muscular tightness, excessive foot pronation, and patellar malalignment. Imaging is seldom needed in special cases. Many possible interventions are recommended for patellofemoral pain management. Due to the multifactorial nature of patellofemoral pain, the clinical approach should be individualized, and the contribution of different factors should be considered and managed accordingly. In most cases, activity modification and rehabilitation should be tried before any surgical interventions.”

In April 2022, a paper in the journal Musculoskeletal science & practice (35) lead by researchers in Queen Mary University London showed that little by way of understanding patellofemoral pain had been made and that doctors were relying on best hope treatments. This is what they wrote:

“Patellofemoral pain is common and has a poor long-term prognosis. There is a lack of clarity about the clinical reasoning of recognized inter-disciplinary experts in the published literature.”

What they are saying is that patellofemoral pain do not have a clear path of treatment. The best treatment plan involves (according to a survey of 19 clinical experts with about 19 years of experience from different medical specialties) the following:

• First, the assessment and diagnosis process should include a thorough history and examination to rule in Patellofemoral pain.
• Secondly, information provision should aim to increase patients’ understanding, aid in controlling symptoms, and facilitate behavior change.
• Thirdly, active rehabilitation, which was a salient theme and included advocacy of combined hip and knee exercise that is adapted to the individual.
• Finally, treatment adjuncts, which can be used selectively to modify symptoms, may include running retraining, taping, or foot orthoses.

We will discuss these treatments below.

The many problems in the knee that surround a patella diagnosis

Typically a patient with knee problems will include among the problems just mentioned in the above research study, other problems including a meniscus tear, knee bursitis, developing osteoarthritis along with a patella diagnosis in their medical history. They will also have, in many cases, a corresponding treatment program for each individual problem.

Other patients we see will simply report that want to be treated for “patellofemoral syndrome,” or “chondromalacia in my patella.” Usually, they contact us after conservative treatments and physical therapy have not helped enough. Sometimes they even contact us after a surgery such as a patella debridement, a tibial tubercle osteotomy, or a patellofemoral ligament reconstruction were tried. (We discuss these procedures below). So their medical history up until the point of contacting our center is one of continued and in some cases severe knee pain, chronic knee swelling, walking difficulties, problems walking up and downstairs, and the near or total inability to run or jump.

A knee pain that no one understands and in some cases, no one believes

Sometimes people will report pain that no one understands and in some cases, no one believes. While we will discuss this at length below, we want to touch on a November 2020 study (3) here to highlight and address this problem.

In this study, researchers at the University of Wisconsin-Milwaukee, Concordia University Wisconsin, and Marquette University outlined the problems of “more pain than the patient with patella disorder should have,” and what may cause it.

Learning points:

• Patellofemoral pain has high recurrence rates and minimal long-term treatment success.
• Central sensitization (heightened pain) occurs when the nervous system, nociceptive neurons (nerve sensation cells) become hyper-responsive.

Complex Regional Pain Syndrome (CRPS)

This study’s aim was to “determine whether the evidence supports manifestations of central sensitization in individuals with Patellofemoral pain. (Simply, is this real?)

The findings?

• “Strong evidence supports lower local and remote pressure pain thresholds, impaired conditioned pain modulation, and facilitated temporal summation in individuals with Patellofemoral pain compared to pain-free individuals.” (These people do have heightened pain).
• Conflicting evidence is presented for the heat and cold pain thresholds.
• Pain mapping demonstrated expanding pain patterns associated with long Patellofemoral pain symptom duration. (it spreads)

Neurophysiological changes of brain and spinal cord in individuals with patellofemoral pain

Research has shown that chronic pain changes brain function. Research also suggests that patellofemoral pain can significantly alter brain function as demonstrated by the above research on Central sensitization (heightened pain). In July 2021 (4) researchers announced their intent to study neurophysiological changes of brain and spinal cord in individuals with patellofemoral pain. This is what the research authors wrote: “Reduced neuromuscular control due to altered neurophysiological functions of the central nervous system has been suggested to cause movement deficits in individuals with patellofemoral pain (PFP). However, the underlying neurophysiological measures of the brain and spinal cord in this population remain to be poorly understood. ” The intent of this research is to understand it better.

A January 2026 study in the journal Clinical biomechanics (37) explored the relationships between kinesiophobia and cognitive-behavioral factors, pain, and functional areas in individuals with patellofemoral pain.  This research was an observational, cross-sectional study that included 66 participants dealing with patellofemoral pain. They were assessed for cognitive-behavioral factors, self-reported pain, knee-related function, and movement function. Analysis revealed a significant negative relationship between self-efficacy (the patients belief that they can or cannot do something) and kinesiophobia. The study results  highlight the complicated nature of kinesiophobia. Enhancing self-efficacy may help reduce fear-related avoidance.

What are we seeing in this chart? You cannot grow knee cartilage in ibuprofen

The simple explanation of this chart is that researchers took dog cartilage cells and tried to grow more cartilage in an ibuprofen solution to test the effect of ibuprofen on cartilage. What did they find out? Ibuprofen reduced the concentration of cartilage glycosaminoglycan. It reduces cartilage growth.

So what do you do about it? You may be surprised that the health care provider is recommending the same over-the-counter pain medications and knee braces and knee pain treatments you tried on your own that did not work for you.

Some patients report the frustration of going from specialist to specialist and still getting the same recommendations for treatment, or better understood as “pain management,” that has not worked for them before and is in fact part of the reason they are going from specialist to specialist.

Suggested treatments that you may be recommended over and over.

• RICE and PRICE
  • The RICE Protocol is Rest, Ice, Compression, and Elevation
  • The PRICE Protocol adds Protection (brace or cast), Rest, Ice, Compression, and Elevation
  • For many athletes, a doctor’s recommendation of the RICE protocol for healing their sports-related soft tissue issue injury was seen as the gold standard of care. However, this treatment is now under criticism. Please see our article for why we do not typically recommend RICE or PRICE.
• NSAIDs
  • NSAIDs are also something we would not typically recommend as chronic non-steroidal anti-inflammatory drugs (NSAIDs) usage can make the pain worse in the long term. Please see our article, When NSAIDs make the pain worse. Regardless, you may have tried to give these treatments one more chance. When they continue to fail, then you decide something more needs to be done. You get a prescription for physical therapy.

Physical therapy? Physical therapy will typically fail if the strong connective ligament and tendons needed to provide resistance to maximize muscle gain and knee stability are not strong enough.

What are we seeing in this image?

The patella is pulled and pushed in all directions. It is pulled by the Iliotibial band, it is stabilized in place by the lateral patellar retinaculum and the medial patellar retinaculum. The quadriceps move the patella upwards, the patellar ligament moves it downward. When one of these structures is weakened or damaged through degenerative wear and tear, the knee cap becomes unstable.

Physical therapy is a very appealing option because it is exercise and people believe exercise is always beneficial. If you are reading this article physical therapy has likely failed you as well.

• Physical therapy includes leg extensions and stretching exercises to help strengthen the thigh muscle, so the patellae or kneecap, tracks better on the femur – it doesn’t scrape the thigh bone.
  • Physical therapy seeks to strengthen the quadriceps as these muscles are the main stabilizers of your kneecap. Physical therapy will have limited or no success if the quadriceps tendon, the tendon that connects the “quads,” the vastus lateralis, vastus medialis, vastus intermedius, and the rectus femoris muscles to the knee cap are weakened. For physical therapy to work, there must be some resistance between muscle and bone. If the quadriceps tendon is damaged, injured, stretched, or harmed in a significant way, physical therapy will have limited if no success.
• Physical therapy will also not work if the ligaments of the knee are compromised or weakened. Ligaments, such as the anterior cruciate ligament (ACL), Medial Collateral Ligament (MCL), Posterior Cruciate Ligament (PCL), hold the knee together by connecting the bones.
• Muscle-strengthening exercises may improve the relative location of the patella upon movement, but do not improve the tendons, ligaments, or cartilage.

Physical therapy will typically fail if the strong connective ligament and tendons needed to provide resistance to maximize muscle gain and stability are not strong enough. We will address this problem and offer our evidence for regenerative medicine injections to correct this problem below.

Exercise can work in some

Doctors at the School of Sport and Exercise Sciences, Liverpool John Moores University examined the effectiveness of exercise in patients in 27 patients with patellofemoral pain. To see if the exercise program was effective they looked for pain reduction, improvement in function, a reduction in kinesiophobia (our fear of movement) among signs that symptoms were getting better.

These are the results they published in the journal Physical Therapy in Sport (5) July 2021. “The results of this study demonstrate that the current exercise recommendations can improve function and kinesiophobia and reduce pain and atherogenic muscle inhibition (a weakness or atrophy in the quadriceps muscle) in individuals with patellofemoral pain. There is a need for reconsideration of the current exercise guidelines (look for more aggressive exercise types) in stronger individuals with patellofemoral pain.

In November 2021, doctors writing in The Journal of the Pakistan Medical Association (6) examined the effects of tibiofemoral (thigh-shin articulation or bend) joint mobilization on pain and range of motion in patients with patellofemoral pain syndrome. In this paper, doctors found “Tibiofemoral joint mobilizations with hip and knee stretching and strengthening exercises were found to be more effective in reducing pain, and increasing range of motion as well as pressure pain threshold. ”

Trigger points and instrument-assisted soft tissue mobilization

A December 2025 study (32) in the Journal of manual and manipulative therapy assessed the combined effects of trigger point dry needling and instrument-assisted soft tissue mobilization on pain and function in individuals with patellofemoral pain syndrome. A single-blinded, randomized controlled trial was carried out involving 102 participants aged 15 to 25 who were diagnosed with patellofemoral pain syndrome. The participants were randomly divided into four groups: one group received trigger point dry needling, another group underwent instrument-assisted soft tissue mobilization, a third group received both treatments, and the last group served as a control. Each intervention group participated in two treatment sessions per week for four weeks, along with a standardized exercise program that all groups followed. The primary outcome measured was the pressure pain threshold (PPT), and secondary pain scores were evaluated at the start and after the intervention.

Results showed that the group receiving both trigger point dry needling and instrument-assisted soft tissue mobilization had the most significant improvements in both measures: the pressure pain threshold increased by 78%, and the pain scores improved by 39% in this combined group. In contrast, the trigger point dry needling group experienced a 53% increase in pressure pain threshold and a 24% rise in pain scores, while the instrument-assisted soft tissue mobilization group had a 54% increase in pressure pain threshold and a 25% increase in pain scores.

Using painkillers – Doctors issue concerns and warnings – Approximately one in five adolescents with longstanding knee pain reported pain medication use.

A December 2021 study from Aalborg and Southern Denmark Universities in Denmark published in the medical review Scandinavian Journal of Pain (7) has doctors expressing concerns that “the prevalence of pain medication use for adolescent knee pain and factors associated with use are not well understood.” In other words, there is a problem specifically in adolescents (age 10-19) with longstanding knee symptoms.

• In this paper 323 adolescents (73% female), 84% had patellofemoral pain (peri- or retro-patellar pain during loaded bending of the knee).
• Twenty-one percent of adolescents reported pain medication use for their knee pain.
• Adolescents with patellofemoral pain reported greater usage than their counterparts with Osgood-Schlatter Disease.

“whether pharmacological therapy is the best pain management option at this young age is debatable”

Conclusions: “Approximately one in five adolescents with longstanding knee pain reported pain medication use, particularly in adolescents with patellofemoral pain. Knee-related symptoms most consistently associated with the use of pain medications in this population . . .Self-reported pain medication use is common in adolescents with longstanding knee pain, even though whether pharmacological therapy is the best pain management option at this young age is debatable. Reliance on pain medication at an early age could potentially hamper the development of healthy pain coping strategies and increase the risk of dependence and misuse later in life.”

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Patients waiting for an MRI delay exercise and physical therapy while waiting outcomes. Some researchers say this is no good

In July 2021 doctors at the Science in Physical Therapy, Bellin College, The University of Newcastle, Tufts University School of Medicine, and Baylor University say routine knee radiographs should be discouraged for individuals with non-traumatic knee pain, but they are often still ordered despite limited evidence for their value in guiding treatment choices. Writing in the PM & R: The Journal of Injury, Function, and Rehabilitation, (8) they further suggest: “Radiograph utilization may delay the use of physical therapy, which has been associated with improved outcomes. . . The research concludes: Routine use of radiographs for PFP is not warranted, and can potentially delay appropriate treatment.”

The MRI will not see your knee pain getting worse and it will confuse you and your doctor

When we talk about MRIs it is often best to listen to radiologists and the surgeons that rely on the MRI for surgical or non-surgical recommendations. In 2012 Doctors at the Finish Institute of Military Medicine published research (9) that found that MRI was ineffective in helping doctors determine the extent of injury in instances of chondromalacia patellae.

In 2018, as well as in 2020, the problem remained. In The Eurasian Journal of Medicine, (10) doctors in Turkey announced: “as chondromalacia stage advances, the symptom severity worsens and knee functions decline; however, MRI measurements do not show the difference between early and advanced stage chondromalacia patella patients.”

Will a knee brace or tape hold my knee together, even with “appropriate caution?”

In physical therapy, strong connective ligaments and tendons are needed to provide resistance. In normal everyday movement, strong connective ligaments and tendons are needed to hold the knee stable and together. Some believe an external brace or tape may help do this job:

Research in the medical journal Joints, (11) suggests that you may benefit from a knee brace or some type of elastic knee sleeve for your patella-related knee pain and help you return to your sport. Many of you reading this article are probably behind a knee brace or sleeve helping.

Doctors at Queen Mary University of London wrote in the medical journal Sports Medicine (12) that doctors “with appropriate caution” should consider brace and taping:

• Offer taping for those patients with greater pain,
• Offer orthoses (knee braces) for older individuals and exercise for younger individuals, and
• Offer orthoses (foot inserts) intervention for patients with greater forefoot and rearfoot abnormalities.

Why the caution? Because there is no good evidence that these treatments work for everyone. Further taping and bracing provide a false sense of stability and can lead to greater knee damage.

Knee braces do provide relief from fear

Some people will need a knee brace but it may be more of a physiological than functional need. In April 2020, researchers published in the Archives of Physical Medicine and Rehabilitation (13) the outcomes of people with patellofemoral pain wearing a knee brace for two weeks compared to a group of people who had patellofemoral pain and did not wear a knee brace for two weeks. Results found that knee braces reduced kinesiophobia (fear of movement) in people with patellofemoral pain after two weeks of wearing one and at a six-week follow-up. The researchers concluded that “a knee brace may be considered within clinically reasoned paradigms to facilitate exercise therapy interventions for people with Patellofemoral Pain.” In other words, if the knee brace gives them the confidence to exercise, that would be okay.

Photobiomodulation – Low Level Laser Therapy

A December 2025 study in the Journal of clinical medicine (31) assessed the efficacy of photobiomodulation on pain and functionality in individuals suffering from Patellofemoral Pain Syndrome. The primary and secondary outcomes evaluated were pain and functionality, respectively. A total of eight trials involving 340 participants met the inclusion criteria.

Photobiomodulation significantly alleviated pain when compared to the control group. Functional outcomes indicated a notable improvement favoring photobiomodulation, although considerable heterogeneity was observed. The combination of photobiomodulation and exercise yields enhancements in pain relief and knee functionality for individuals with Patellofemoral Pain Syndrome. While the results endorse photobiomodulation as an effective adjunctive treatment, there is a necessity for standardized dosing protocols and larger, high-quality studies to bolster future clinical guidelines.

Retraining the way you run? A recent study kicks off to explore gait training

In May 2021 researchers announced their intent to study the effectiveness of gait training in patients with Patellofemoral pain. (14) Here is the rationale for this study.

“Patellofemoral pain (PFP) is highly prevalent in runners. Physical therapies were proved to be effective in the treatment of Patellofemoral pain. Gait retraining is an important method of physical therapy, but its effectiveness and safety for Patellofemoral pain remained controversial. The previous review suggests gait retraining in the treatment of Patellofemoral pain warrants consideration. However, recent publications of randomized controlled studies and case series studies indicated the positive effect of gait retraining in clinical and functional outcomes, which re-raise the focus of gait retraining.

(The study’s aim) is to publish findings that will provide information about the safety of gait retraining and their effect on relieving pain and improving the function of the lower limb on runners with Patellofemoral pain.

The interest in gait retraining is summarized in a December 2019 study in The American Journal of Sports Medicine (15). This study investigated whether a 10% increase in the running step rate influences frontal-plane kinematics of the hip and pelvis as well as clinical outcomes in runners with Patellofemoral pain.

• Gait retraining consisted of a single session where the step rate was increased by 10% using an audible metronome.
• After gait retraining, significant improvements in running kinematics and clinical outcomes were observed at 4-week and 3-month follow-up.
• These improvements were maintained at a 3-month follow-up. It is important to assess for aberrant running kinematics at baseline to ensure that gait interventions are targeted appropriately.

“Unsatisfactory long-term prognosis of conservative treatment of patellofemoral pain syndrome”

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Why consider these treatments if your chances are 1 in 4 that they will work for you and less that they will get you back to your sport?

In 2018, these same researchers made clear in the journal Physical Therapy in Sport (16)  that: “Long-term (traditional) treatment outcomes of (Patellofemoral pain) are poor, with estimates that more than 50% of people with the condition will report symptoms beyond 5 years following diagnosis. Additionally, emerging evidence indicates that PFP may be on a continuum with patellofemoral osteoarthritis.”

So why are these things not working? The heading above is the title of a research paper from Danish researchers published in the Journal of the Danish Medical Association. (17)

• In this study, the Danish team looked at military personnel, athletes, and the general public to offer doctors a clue to how well or unwell conservative treatments work for patellofemoral pain syndrome.
  • Only 29% of soldiers,
  • Only 27.8% of sports-active and
  • Only 24,7% of the general public will become pain-free after they are diagnosed with patellofemoral pain syndrome.
  • 21.5% of sports-active and 23% of the general public diagnosed with patellofemoral pain syndrome will stop participating in sports because of knee pain.

These are very low numbers. Why consider these treatments if your chances are 1 in 4 that they will work for you and less that they will get you back to your sport?

As mentioned above, supportive knee braces, arch supports, and taping may also be recommended to improve the alignment of the kneecap. The problem with this approach is that they do not repair the deteriorated cartilage in the patellae.

Decreased hamstring strength and symptoms of knee osteoarthritis and patellofemoral pain

A July 2024 study (39) in the Journal of sport and health science focused on hamstring strength, flexibility, and its impact in individuals with gradual-onset knee disorders. In reviewing the data of 79 previously published papers, the researchers assessed patient outcomes in cases of  knee osteoarthritis, patellofemoral pain, chondromalacia patellae, and patellar tendinopathy.

The researchers found:

• Individuals with knee osteoarthritis had reduced hamstring strength compared to pain-free control patients during isometric and concentric contractions.
• Individuals with patellofemoral pain had reduced hamstring strength compared to pain-free controls during isometric,  concentric, and eccentric contractions.
• No differences were observed in individuals with patellar tendinopathy.
• The researchers suggest: “that assessing and targeting impairments in hamstring strength and flexibility during rehabilitation may be recommended for individuals with knee osteoarthritis or patellofemoral pain.”

Unexplained and significant elevation in knee pain that your doctor may not believe

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Something is going on beyond normal biomechanical problems

Your doctor is looking at your MRI. Your knee does not look worse. But your pain is. You are confusing your health care providers as nothing seems to work for you. Maybe this is “all in your head?” because it is not on your MRI.

You may also be researching for your son or daughter who is confusing their doctors with a description of elevated pain that “should not be there.”

Doctors writing in the journal Physical Therapy in Sport, (18) wrote that what your son or daughter is trying to describe as heightened pain, is real. Read this:

“Adolescent athletes presented higher levels of pain and lower physical function status compared with physically active non-athletes. This provides an important insight into the management of (Patellofemoral Pain Syndrome) in adolescent athletes as the worst functional status is linked with poor prognosis in patients with Patellofemoral Pain Syndrome.”

Something is causing more pain in the athletes than the non-athletes.

“The patient often bounces from practitioner to practitioner, physiotherapist as well as surgeon, for some relief of symptoms”

Physiotherapist Jenny McConnell wrote in the medical journal Manual Therapy:(19)

“Although the management of Patellofemoral Pain has improved greatly, there is still a category of patient who tends to have recalcitrant (non-responsive) symptoms, which are difficult to manage. The patient often bounces from practitioner to practitioner, physiotherapist as well as surgeon, for some relief of symptoms. However, often the underlying source of the pain is not well understood, so treatment can aggravate the symptoms.”

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When knee pain is worse than it should be and nothing is working, what next?

Leading university researchers in the United Kingdom and Denmark, working within the UK’s National Health Services at Derby, made some observations of the patient’s mindset in regard to his/her diagnosis of Patellofemoral Pain Syndrome. (20) These published 2018 findings are similar to what we see in patients here at Caring Medical. Something is going on beyond normal biomechanical problems. Here is the UK research:

• Participants offered rich and detailed accounts of the impact and lived experience of Patellofemoral Pain Syndrome, including:
  • loss of physical and functional ability;
  • loss of self-identity;
  • pain-related confusion and
  • difficulty making sense of their pain;
    • pain-related fear, including fear-avoidance and ‘damage’ beliefs;
    • inappropriate coping strategies and fear of the future.

The researchers concluded: “The current consensus that best-evidence treatments consisting of hip and knee strengthening (physical therapy and exercise) may not be adequate to address the fears and beliefs identified in the current study.

Patellofemoral pain syndrome impacts the whole body

In a third 2018 study, doctors at the Erasmus University Medical Center in The Netherlands published findings that help understand patellofemoral pain syndrome impacting the whole body. Publishing in the journal Pain Medicine,(22) the Dutch team found knee and generalized (whole-body) stress and overload hyperalgesia in these patients suggesting the knee pain caused alterations in both peripheral (musculoskeletal nerves outside of the brain and spinal cord) and central pain (nerves in the central nervous system) processing.

• What this all means is that continued stress on the knee accelerated pain sensitivity. You feel more pain than the damage to the knee should be causing.

These troubling findings were expanded on in research published in May 2017 in the British Journal of Sports Medicine where the physiological component of Patellofemoral Pain Syndrome was examined:

• “Anxiety, depression, catastrophizing and fear of movement may be elevated in individuals with Patellofemoral Pain Syndrome and correlate with pain and reduced physical function.”(23)

Patellofemoral cartilage surgery?

For many people, surgery may or “will have to be recommended.” For many people, surgery will be a successful procedure and meet their expectations and hope. We typically do not see patients who had successful surgery. We see the patients who did not, have lingering complications or a general sense of instability about the knee.

For a frustrated athlete, the call of surgery is strong. Surgery, however, is usually not indicated for Patella Pain Syndrome unless the non-surgical treatment options we explored earlier in this article have been exhausted.

When we discuss surgery it is always best to bring in surgical consults from medical research.

“Unrealistic expectations are common and will lead to disappointment.”

In June 2018, research led by Harvard Medical School published in the journal Current Reviews in Musculoskeletal Medicine (26) warned surgeons and patients, especially athletes, to have a realistic expectation of what cartilage repair in the patellofemoral joint surgery can really offer them:

“Cartilage repair in the patellofemoral joint has demonstrated increasingly good outcomes in patients with patellofemoral cartilage defects after conservative treatment has failed. . . It is of utmost importance to discuss with the patient current functional limitations in sports and activities of daily living, to elucidate the patient’s goals and expectations, and to go over the rehabilitation and recovery time.

Unrealistic expectations are common and will lead to disappointment.

Careful evaluation of the knee and lower extremity, through physical examination and imaging studies, is crucial. This will allow planning a comprehensive treatment approach for the cartilage repair procedure, as well as any additional pathology that needs to be addressed in a staged or concomitant fashion.”

What is being said here is that the surgery is usually successful as far as surgery goes. But it is usually not successful in helping the patient/athlete with their goals have had the surgery. To get back to sports or work quickly. “Unrealistic expectations are common and will lead to disappointment.”

The prevalence and change in neuropathic pain or pain catastrophizing before and 12 months following patellar stabilization surgery for patellofemoral instability

A July 2021 paper in the journal International orthopaedics lead by University of Oxford (36) attempted to determine the prevalence and change in neuropathic pain or pain catastrophizing before and 12 months following patellar stabilization surgery for patellofemoral instability.

• Data from 84 patients with patellofemoral instability requiring stabilization were analyzed.
  • Fifty percent (42/84) underwent Medial Patellofemoral Ligament (MPFL) reconstruction alone, and
  • 16% (13/84) had both trochleoplasty (surgery that creates or deepen the groove in the trochlea to prevent recurrent patella dislocations) and MPFL reconstruction.

Results:

• At 12 months post-operatively there was a statistically significant reduction in average Pain Catastrophizing Scores but no change in average pain scores. There was a statistically significant improvement in better stability and function scores.
• The prevalence of pain catastrophizing decreased from 31% pre-operatively to 24% post-operatively, whereas the prevalence of neuropathic pain remained consisted (10-11%).

Conclusions:

• Neuropathic pain and catastrophizing symptoms are not commonly reported and did not significantly change following patellofemoral stabilization surgery. Whilst low, for those affected, there remains a need to intervene to improve outcomes following patellofemoral instability surgery.

“This rise in surgical intervention has brought about various complications.”

In the journal Sports Medicine and Arthroscopy Review, (March 2017) (27) Dr. Nick Caplan Ph.D., wrote:

“In recent years, surgical interventions for patellofemoral joint instability have gained popularity, possibly revitalized by the recent advances in our understanding of patellofemoral joint instability and the introduction of a number of new surgical procedures. This rise in surgical intervention has brought about various complications.”

Dr. Caplan and his associates went on to describe the various complications associated with certain surgeries including:

• Patella-medial patellofemoral ligament reconstruction
  • This is a surgery usually reserved for knee cap dislocation. As patella pain syndrome may have patellar maltracking is a cause, this is where the patella moves out of its groove resulting in damage to the cartilage that covers its back, it is thought that surgical replacement of the patella-medial patellofemoral ligament will provide ample stability to the knee cap and alleviate pain.
  • While we agree that the patella-medial patellofemoral ligament plays a major role in providing pain-free knee movement. We do not agree that surgery is the best way to repair it unless there is a complete “disintegration” injury. In this type of injury, the ligament literally explodes and there is nothing left to repair.
  • We have an extensive article on Surgery and non-surgical treatments for acute and chronic knee cap dislocation that explains this procedure further.
• Tibial tubercle osteotomy
  • In this surgery, the patella tendon is moved by slicing off the bone it attaches to, moving it on the shin bone (tibia), and then reattaching the bone with the tendon to the shin bone with a screw.
  • The goal of this surgery is to provide stability to the knee by using the re-positioned tendon to hold the patella in the correct position on the knee.

Younger patients have better surgical results, but what do you do with older patients? Patellofemoral arthroplasty?

In November 2019, (28) orthopedists at the State University of New York at Buffalo published a study suggesting “that patients have improved clinical outcomes after microfracture of symptomatic patellofemoral chondral lesions at midterm follow-up. Our review also found some evidence to suggest that younger patients may have improved clinical outcomes that are more durable over time compared with older patients. However, we could not draw any definitive conclusions regarding the effect of location, size, or severity of the chondral lesion.”

Older patients may not fare as well. So what do we do with them? Knee cap replacement?

Patellofemoral arthroplasty or “knee cap replacement,” is a surgery that can be performed in isolation if the patella osteoarthritis is the main cause of a patient’s pain. It is usually reserved for older patients for whom microfracture or arthroscopic patella surgery was not or is deemed to not be successful.

Botulinum toxin injections as a salvage therapy

An October 2021 study (29) from leading Israeli universities and New York University NYU Langone Orthopedic Hospital and published in the journal Knee surgery & related research examined the imbalance between the vastus medialis oblique (one of the four quadricep muscles) and the vastus lateralis (the largest of the quadriceps muscles). It is this imbalance that can lead to patella malalignment and considerable pain and reduced quality of life. This study tried to determine the effectiveness of botulinum toxin injections in patients, average age 50, treated with a botulinum toxin injection and then physical therapy. What the researchers found that in selected patients a single intervention of botulinum toxin injection to the vastus lateralis muscle combined with physiotherapy is beneficial for the treatment of patients with persistent and difficult to treat Patellofemoral Pain Syndrome.

What this study expressed is a problem of instability and imbalance because one muscle tugged harder on the patella than the other. The same can be true for ligaments.

Solving Patellofemoral Pain Syndrome is recognizing the problem of knee instability

We are going to look at the problem of Patellofemoral Pain Syndrome as a problem of knee instability. A problem that can be treated with regenerative medicine injections beyond botulinum toxin injection.

In the research above we mentioned that knee braces or sleeves could provide some temporary relief especially psychologically. Medical university researchers shared their observations on what a knee brace could do for patellofemoral pain symptoms.

Writing in the European journal Gait Posture published by Oxford University, the researchers discovered that the most beneficial aspect of wearing a brace was during walking and that the brace helped coordinate muscle activity around the knee. (30) This theory was tested among 12 women aged 20-30 years with a diagnosis of patellofemoral pain.

• What is this study suggesting the knee brace provides stability so the muscles could function correctly. Of course, knee braces are not long-term treatments for knee cap instability. Treatments that stabilize the knee by strengthening the ligaments and tendons are.

Comprehensive Prolotherapy for Patellofemoral Pain Syndrome – treating the whole knee

Research: “. . . patients with chondromalacia patella who received Prolotherapy reported a significant decrease in their levels of pain at rest, normal activity, and exercise, in addition to an improvement of range of motion, decrease in knee stiffness, and reduction in crepitus.”(29)

Please read more

Prolotherapy for knee instability in Patellofemoral Pain Syndrome

Recommendation to a third knee surgery: When the patella pain does not respond to conservative care treatments

In the image below we see an x-ray revealing chondromalacia patella and bone spur in a 66 year-old female patient who was seeking treatment for knee osteoarthritis pain and a grinding sensation under her kneecap. Patient had two previous knee surgeries. She was getting minimal improvement from Prolotherapy treatments, To assess her situation, an x-ray was ordered. The x-ray revealed minimal joint space under her kneecap consistent with chondromalacia patella and the grinding sensation she experienced. Notice also the hook bone spur offer patella. Because of the abnormality of the bone spur, continuing Prolotherapy was not the best treatment option for her and despite two previous surgeries, she needed an orthopedic consult.

PRP and Prolotherapy

• PRP treatment takes your blood, like going for a blood test, and re-introduces the concentrated blood platelets from your blood into areas of chronic joint and spine deterioration.
• Your blood platelets contain growth and healing factors. When concentrated through simple centrifuging, your blood plasma becomes “rich” in healing factors, thus the name Platelet RICH plasma.
• The procedure and preparation of therapeutic doses of growth factors consist of an autologous blood collection (blood from the patient), plasma separation (blood is centrifuged), and application of the plasma rich in growth factors (injecting the plasma into the area.) In our office, patients are generally seen every 4-6 weeks. Typically three to six visits are necessary per area.

PRP as we perform it is NOT a single injection. It is a comprehensive treatment that addresses problems, weakness, and instability of the whole knee capsule.

• We typically treat the anterior and posterior of the knee (the front and back)
• Some injection areas included in the treatments are at the lateral condyle of the tibia to get to one of the attachments of the anterior cruciate ligament.
• Knee instability is a common condition that causes chronic knee pain so when a person is getting treated for knee instability you have to make sure that the various ligaments that are causing the instability are being treated.
• Other attachments of the anterior cruciate ligament are treated.
• Platelet-rich plasma is very effective at helping resolve any issues that relate to knee instability especially of the cruciate ligament specifically the anterior cruciate ligament as well as meniscal tears and degenerated meniscus.
• This particular person has knee instability from primarily the anterior cruciate ligament being lax or injured. That injury will also cause instability to occur in the medial-lateral collateral ligament. This is why we treat the lateral knee and the medial knee and the attachments of the medial collateral ligament.

PRP injections and one injection of hyaluronic acid

A May 2024 study published in the Archives of orthopedic and trauma surgery (38) investigated the effect of PRP on patients with anterior knee pain.

• 43 patients with anterior knee pain 28 patients in the injection group and 15 patients who received physical therapy.
• Of the 28 patients in the experimental group, they received three PRP injections and one injection of hyaluronic acid.
• Although an improvement was seen in both groups, a statistically significant difference favoring the injection of PRP over the PT-only group was observed.
• The superiority of outcomes in the injection group was observed at 3 and 6 months after the initial diagnosis was made. Furthermore, the results of this study revealed a significant improvement at 3 and 6 months when compared to baseline measures.

The Use of Prolotherapy for Chondromalacia Patella (Patellofemoral Pain Syndrome)

In 2018, our research team published new findings in the Journal of Prolotherapy. (33) Here we found:

• In summary, the outcomes of this study illustrated that Prolotherapy may be an effective treatment for reducing the symptoms of chondromalacia patella.
• The observed decreases in symptoms of patients who received Prolotherapy were shown to be highly significant.
• The patients in this study who received Prolotherapy improved in the overall level of pain, function, and mobility in the case of chondromalacia patella.
• These improvements were seen in varying durations of initial pain and treatment and gender.
• Improvements observed with Prolotherapy were seen in patients of all ages, making the potential benefits of Prolotherapy generalizable to the majority of the U.S. adult population.

Bone Marrow Aspirate or Bone Marrow Stem Cell Therapy.

Stem cell therapy can be an effective treatment for some patients, it can also easily fail as a treatment in some patients. We have two extensive articles on our website that can explain who stem cell therapy can and cannot help and why the treatment may fail. Please see When stem cell therapy works and does not work for your knee pain and Does stem cell therapy for knee meniscus tears and post-meniscectomy work?

For more on stem cells, please see the article below.

Bone Marrow Stem Cell Therapy for chondromalacia patella

Can we help you?

If this article has helped you understand treatment options for Patellofemoral Pain Syndrome and chondromalacia patella and you would like more information, you can get help and information from our specialists

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